Electromagnetic switch.



'No- 852,582. PATENTED MAY 7, 1907. y

W. SGRIBNER.

ELECTROMAGNETIC 'SWITOH. APPLICATION FILED DBG.1.1905.

mum-mum.

ATTORNEYS WALTER SCRIBNER, OF COLUMBUS, OI-IIO.

ELECTROMAGNETIC SWITCH.

Specification of Letters Patent.

Patented May 7, 1907.

Application filed December 1,1905. Serial No. 289.912.

T0 aZZ whom it 7-way concern.-

Be it known that I, WALTER SGRIBNER, a

citizen of the United ,States, residing'at Columbus, in the county ofFranklin and State of Ohio, have invented pertain new and usefulImprovements in Electromagnetic Switches, of which the following is aspecification. My invention relates to new and useful improvements inelectromagnetic switches.

It is a well known Tact that in order. to

charge a set of storage batteries, the voltage of the charging currentmust be hi her than that normally given out by the batteries, thereforeit is practically impossible to use the current from the batteries whilethe same ,are being charged, as the high voltage would burn out thelamps or other devices connected with the batteries. Several methodshave been employed for reducing the voltage of the current from abattery or batteries while the batteries.

With the above and other objects in view, the invention consists of thenovel details of construction and operation, a referable embodiment ofwhich is describe in the specification and illustrated in theaccompanying drawings, wherein:

Figure 1 is a side elevation of the device,

the electro-magnet being shown in vertical section and the batteries,lamps and their connect ons in diagram. Fig. 2 is an end elexation ofthe device, and, Fig. 3 is an elevation of the opposite end.

In carrying out my invention, as an illustration, we will take thrty-two cells of 280 ampere hour storage batteries connected in series,which give out a maximum of 70.4 volts when fully charged. These cellsare indicated in the drawings by the numeral 1. This maximum voltage,however, is not maintaincd, but drops gradually as the current is usedfrom. the batteries until it becomes necessary to charge the same againand in order that the lamps indicated by the numeral 2 may derive abouttheir normal voltage as long as possible, a lamp is usually selected.

requiring somewhat lower than the maximum battery voltage. In thisinstance of a set of thirty-two cells of batteries, we will select alamp voltage of 65. The normal charging rate of this set of 280 amperehour batteries is 35 amperes, which requires a potential of about tovolts on the charging current. that the potential of 90 to 95 voltsrequired to charge the batteries, would bedetrimental to the life of the65 volt lamps or other apparatus deriving its source of power from thebatteries; that is, should it be desired to use the lamps while thebatteries are being Hence it will be readily seen charged. Ashereinbefore stated, various resistance materials have been used in thelamp or other circuits for reducing the voltage while the batteries arebeing charged.

I will now proceed to describe my invention in detail. It is usual toprovide .a suitable charging receptacle,.which I have indicated by thenumeral 3. The lead wires from the dynamo are inserted in thisreceptacle when-it is desired to charge the batteries. From the chargingreceptacles a positive charging wire 4 extends to the terminal post 5 ofa suitable electro-magnet 6, while a negative charging wire 7 extendsfrom the receptacle to the batteries. The electro-magnet 6 as will beapparent forms part of an automatic switch which comprises an armature 8extending along its underside and suitably connected at its rear end toa hinge 9 fixed on the rear side of the magnet 6 as best shown in Fi 3.abut the pintle 11 of the hinge has one end looped about a screw 12 setinto the rear face of the magnet 6 and ,the opposite end extendedbeneath the armature and engaged in an eye 18 projecting downwardly fromsaid armature. This "spring normally tends to swing the armaturedownward when the batteries are not charging. On its forward end whichprojects beyond the magnet, the armature 8 carries and is surrounded bya block of fiber or. other suitable insulating material 14. A U-shapedcontact plate 15 is engaged about the fiber on its upper and lower sidesand outer'end as clearly shown in Fig. 1. To the side or forward end ofthe magnet 6 astrip of fiber or other insulating material 16 is secured.This strip projects some distance below the magnetand supports asubstantially U- shaped terminal 'A suitable wire spring 10 coiled 7 setscrew 21.

- terminal plates 17 and 18, .I mount similar" 5 strip 16 as clearlyshown "in,

' strip of the armature.

' positive wire plate 17 directly beneath the contact plate contactplate an open ended housing 19 in which a strip of carbon 20 is rigidlyheld by a The carbon has such a length as to project slightly above andbelow the contact plate'15. On the face or ends of the housing 22 and 23in which carbon strips 24 and 25 are mounted to slide. Each of thesestrips is provided with a central slot 26 indicated in dotted linesthrough which a set screw 27.is passed from the housings. Flat curvedsprin .s 28' are let into the housings having their ice ends bearing onthe carbon strips 24 and 25 and their fixed ends secured by set screws29lfastened in an insulating Fig. 2. These springs are arranged so asto. tend to force the carbon strip 24 upward and the carbon strip 25downward and are of light construction so 'a'sto yield and permit thecarbonstrip 25 tobe pressed, upward when engaged by .the strip 20 of thearmature and. the strip .24 pressed downward when engaged by the said Inthis manner when the armature isswung downward, its carbon strip 20,will first engage the carbon strip 24 and force the same downward untilthe contact plate 15 engages with the terminal plate 17 and likewisewhen the armature is swung upward, the plates will be pulled apart be-28 will carry the strip 24 upward the length of the slot 26 before thecarbon20 is disengaged therewith, thus holding the contact until. afterthe plates are pulled apart thereby preventing arcing between the metalcontact plates and detrimental effects. tion will be the same when thearmature is moved down and up. Suitable binding posts 30 and 31 aresecured to the terminal plates 17 and 18, while a third binding post- 32is supported by the block of fiber 14 and connected with the contactplate 15.

Having described the details of the automatic switch, I will now proceedto describe the connections and the operation of the same; The lamps 2are connected with the negative charging wire 7 by a negative Wire 7,while a 33 leads from thelamps to the binding post 32 of the armaturecontact plate 15. A positive battery wire 34 leadsfrom the batteries tothe binding post 5 the electro-magnet 6. From the positive wire 34 apositive battery wire 34 extends to'the binding post 30,while aspecialpositive wire The operaminal points of the wires 34 and 35.

35 extends from the binding post 31 to the batteries. This special wireis connected to the positive terminal of one of the cells of thebatteries. In this instance I have shown it attached to the. positiveterminal of the .lifth cell from the left, which gives suflicientreduction in the voltage for the purposes desired. In explanation ofthis, it is understood that in charging a set of batteries there isa certain potential drop across each cell. When the batteries are charging atthe normal rate of thirtyfive ainperes, the potential drop across eachcell will be three volts; thus by tapping into the fifth cell, areduction of about fifteen volts will be had.

I will now proce ed'to describe the operation of my device: Beginning atthe charging receptacle 3, it will be noted that thepositive current isconveyed by the wire 4 to the bind' ing post 5 through the magnet 6 tothe binding post 5 and over the wire 34 which extends therefrom to thebatteries 1 from thence to the negative charging wire Tand thereceptacle 3. Of course it will be understood that when the lead wiresfrom the dy-- namo are first inserted in t 1e charging recepe tacle 3the magnet 6 is not charged and therefore-the spring '10 will have swungthe armature 8 down so that the contact plate 15 is in contact with theterminal plate 17, thus the positive current passing along the wire 34will also pass along the positive wire 34' to the. binding post" 340through the plates-to the binding post 32 and over thepositive lamp wire33 to the lamps. After passing through the lamps thecurrent will becarried by the negative lamp wire 7 to the negative charging wire 7 andthus back to the dynamo. However, when the current passes through themagnet 6,thesame ischarged or energized, so that the armature 8 is drawnupward pulling the contact plate 15 from the terminal plate 17 andthrowing it into contact with the terminal plate '18 in consequence ofwhich the wire 34 becomes idle, while the'circuitis closed from thefifth'cell through the'special wire 35 to the binding post 31 and theterminal plate 18.- In this. manner the current which passes to the lamphas all the voltage except the first five cells, it being obvious thatthe current carried by the special wire 35 after passing over the plate18 passes to the armature contact plate 15, the binding post 32 and byway of the lamp wire 33 to. the lamps. It'is obvious that the voltage ofthe current passing to the lamps may be increased by including a greaternumber of cells or reduced by diminishing the number of cells betweenthe ter When the charging wires from the dynamo are dis- I connectedfrom the charging receptacle 3, the electro-magnet 6 will be immediatelydeenergized so that the spring 10 will swing the armature 8 downwardbreaking the circuit through the special wire 35 and closin it throughthe Wires 34 and 33 as hereinbeiore described. v

WVhile the automatic switch forming the present invention has been-shownin connec- I t1on with a lighting system, 1t s to be understood that itmay be used for other purposes if desired.

.VVhat I claim, is: A switch comprislng an electro-1nagnet, an

' armature arranged to be attracted by said other side of the armature,the contact plate carried by said armature being adapted to contact withone of these fixed contact plates at each limit of its movement, meansfor connecting an electrical conductor to'each of the fixed contactplates and to the contactzplate of the armature, and a carbon strip sliably and yieldingly mounted upon the outer face of each of thefixedcontact plates withwhich the carbon strip carried by the contact plateof the armature is adapted to.contact prior to the contacting of thecontact plates with each other.

In testimony whereof I affix my signature in presence of two Witnesses.

WALTER scRIBNER."

Witnesses:

A. L. PHELPS; M. B. SoHLnY;

